<template>
    <div class="cmt-container">
        <h3>发表评论</h3>
        <hr>
        <textarea placeholder="请输入要评论的内容（最多120字）" maxlength="120" v-model="msg"></textarea>
        <mt-button type="primary" size="large" @click="postComment">发表评论</mt-button>
        <div class="cmt-list">
            <div class="cmt-item" v-for="(item,i) in comments" :key="item.add_time">
                <div class="cmt-title">
                    第{{ i+1 }}楼&nbsp;&nbsp;用户：{{ item.user_name }}&nbsp;&nbsp;发表时间：{{ item.add_time|dateFormat }}
                </div>
                <div class="cmt-body">
                    {{ item.content==='undefined'?'此用户很懒，啥都没说':item.content }}
                </div>
            </div>
        </div>
        <mt-button type="danger" size="large" plain @click='getMore'>加载更多</mt-button>
    </div>
</template>
<script>
import Toast from "mint-ui"
export default {
    data(){
        return {
            pageIndex:1,   //默认展示第一页数据
            comments:[],
            msg:''  //评论输入的内容
        }
    },
    created(){
        this.getComments();
    },
    methods:{
        getComments(){
            this.$http.get("api/getcomments/"+this.id+"?pageindex="+this.pageIndex).then(result=>{
                if(result.body.status===0){
                    this.comments=this.comments.concat(result.body.message);
                }else{
                    Toast('获取评论失败！')
                }
            })
        },
        getMore(){
            this.pageIndex++;
            this.getComments();
        },
        postComment(){
            //校验是否为空内容
            if(this.msg.trim().length===0){
                return Toast('评论内容不能为空！')
            }
            //参数1：请求的URL地址
            //参数2：提交给服务器的数据对象，{content:this.msg}
            //参数3：定义提交时候表单中数据的格式{emulateJSON:true}
            this.$http.post('api/postcomment/'+this.id,{content:this.msg.trim()}).then(function(result){
                if(result.body.status===0){
                    //1.拼接出一个评论对象
                    var cmt={
                        user_name:'匿名用户',
                        add_time:Date.now(),
                        content:this.msg.trim()
                    };  //如果将来有登录功能，从session中取用户名
                    this.comments.unshift(cmt);
                    this.msg=""
                }
            })
        }
    },
    props:["id"]
}
</script>
<style lang="scss" scoped>
    .cmt-container{
        h3{
            font-size:18px;
        }
        textarea{
            font-size: 14px;
            height: 85px;
            margin:0;
        }
        .cmt-list{
            margin:5px 0;
            .cmt-item{
                font-size: 13px;
                .cmt-title{
                    line-height: 30px;
                    background-color: #ccc;
                }
                .cmt-body{
                    line-height: 35px;
                    text-indent: 2em;
                }
            }
        }
    }
</style>